Suspected Thread Border Router failure after tvOS 27.2
My Apple TV 4K 2nd generation (A2169) automatically updated to tvOS 27.2. All 10 Matter devices previously worked normally, but I subsequently discovered that all were offline in both Apple Home and Home Assistant.
The Apple TV remains connected as a Home hub, and AirPlay/mDNS services are discoverable.
However, the Thread Border Router service _meshcop._udp.local is no longer discoverable from macOS or Home Assistant.
Troubleshooting already completed:
- Cold-restarted the Apple TV.
- Switched from Ethernet to Wi-Fi.
- Confirmed devices are on the same VLAN.
- Checked UniFi multicast settings.
- Confirmed Apple TV's IPv4 and IPv6 mDNS traffic with tcpdump.
- Confirmed the Matter Server is running.
The Apple TV appears not to be advertising its Thread Border Router service following the update.
Could this be a tvOS 27.2 Thread initialization or network-attachment regression? Is there a way to restart or recover the Thread subsystem without factory-resetting the Apple TV or losing the existing Thread network credentials?